In general, existing museum showcases comprise individual drawers that can be independent from the others and serve not only the function of conserving objects, but also making their viewing possible, albeit to a more limited extent compared to a showcase of another type, for example a display case. These showcases are used for objects that are not displayed to the public permanently, for example because they should not be excessively exposed to light or because they are included in very large collections, in which individual objects are only occasionally viewed. Moreover, the drawers can be horizontal or vertical depending on whether they are mutually superposed or set side by side. The drawers can be glass lids openable by tilting, if horizontal, or by rotation if vertical. The vertical drawers can have both sides made of glass and openable. Moreover, the drawers can also be used in composite structures, superposing on them an independent showcase body, not fastened thereto, in one of its numerous variants: with door, glass case, or table. Drawers are positioned on different types of guides, from simple ones made of metal, to telescopic ones, with high performance and with multiple extraction stages. The system for actuating showcase drawers are typically positioned in the part behind the drawer, to allow its extraction and re-insertion in the horizontal direction.
The mechanism for opening and closing the drawers of the showcase must assure that the movements of the drawers, both when opening and when closing, are gradual, i.e. smooth and gentle. With such gradual opening and closing, the objects conserved and displayed in their interior are safeguarded, protecting them from any vibrations or sudden movements. For this purpose, therefore, all drawers are provided with limit switches and braking devices which smooth out their movements. The closure of the showcase drawers can be manual or automatic.
For this purpose, in the prior art manual or motorised actuation systems are used, which assure the extraction and reinsertion of the showcase drawers.
Generally, the manual extraction and reinsertion of the drawers take place by means of metallic bar handles or retractable handles, obtained in the thickness of the front panels of the drawers; the automatic extraction and reinsertion take place through the use of specific electromechanical motors.
Hence there is the problem of using actuating systems that minimise vibrations and sudden movements of the drawers when opening and closing, hence limiting acceleration at any point of the travel, thus making these showcases compatible with the requirements for a correct maintenance of the objects conserved and displayed in the drawers.